Within the space of most three-hour operas, revolutions can be plotted and dynasties overthrown; lovers can meet, betray each other and be reconciled. But in the opening part of The Peony Pavilion, a nine-hour opera that runs over three performances, all that happens is that its heroine, Du Liniang, is granted a fleeting vision of love and afterwards pines away with a broken heart.

Time passes slowly in kunqu, the early classical form of Chinese opera, despite the fact that the producers of The Peony Pavilion have cut the original running time by half. There are other concessions to modern taste, too, in the mix of contemporary and traditional instruments and in the impeccable aesthetic of the lighting and set design. Anyone with the slightest interest in the style pages of magazines will be struck by the beauty of the costumes and painted backdrops here, with their delicate watercolours and minimalist lines.

However, none of these audience-friendly tinkerings blunts the fact that The Peony Pavilion is a very alien kind of theatre. Compared with the more acrobatic Beijing Opera, the singing and movement are contained within a fluttery, low-key style, an exquisite calligraphy of expression. By contrast, the speaking style of kunqu is extravagantly mannered. Characters engaged in the most ordinary of conversations sound like angry gulls, their voices keening and swooping in wild cadences.

Given that most of the action is in the language, the digital subtitles flashing at either side of the stage are a vital prop. Little may be happening on stage, but the language is dense and surprising.

Watching The Peony Pavilion is a hallucinatory, entrancing experience - but not one for the easily bored. A whole scene can pass in flash, but minutes can stretch into hours.